Re: [APML] Large Format Question

["Joseph O'Neil" <joneil@multiboard.com>]

Hi

>1. The lenses for these cameras were generally meant to be stopped down to 
>f/16. Some have nice large apertures for focusing but that's all they're 
>good for. If your lucky you might get away with f/8.

         Aerial camera lenses - if you can find a good one - can be used 
wide open.  the "trick" to them is to find one that covers more than 4x5 
(say 5x7, or 8x8, or whatever weird size  they may have been deisgned for), 
so that your film sits in themiddle, and all the nasty optical abberations 
that are normally seen at the edge of an image circle lies outside the film 
coverage.  Nto always perfect, and a bit of a cheat I suppose, but it works.


>2. Unlike 35mm and medium format, the 4x5 film holders do not have a 
>pressure plate to hold the film flat. The use of small f-stops helps to 
>compensate for this.

         You need either  Lindhof or a Toyo film holder.  The Lindhof ones 
are not made I thik anymore, and the Toyo one is a specail order.   Both of 
them have pressure plates.  Both are expensive and can be ahrd to 
find.  The Lindhof ones also take 4x5 sheet glass plates.
joe







http://www.oneilphoto.on.ca
http://www.multiboard.com/~joneil
"Una salus victus nullam sperare salutem"


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